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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16324 results found.

  1. GRB 181213A: NOT optical observations
  2. GRB 181213A: GWAC-F60A upper limit
  3. GRB 181213A : TSHAO optical observations
  4. GRB181213A: Swift/UVOT Detection
  5. GRB 181213A: BOOTES-5/JGT optical observations
  6. GRB 181126B: KAIT Follow-Up Observations of a Fermi Short GRB (Trigger 564897175)
  7. GRB 181201A: continued optical observations in Mondy
  8. MASTER OT J063515.49-624002.9 of Fermi trigger 565936249: optical observations in SAAO
  9. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  10. GRB 181201A: VLA detection
  11. GRB 181201A: ALMA detection of a fading mm afterglow
  12. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  13. GRB 181201A: continued optical observations in TSHAO and Chilesope
  14. GRB 181203A: BOOTES-3/YA optical observations
  15. GRB181201A: Optical afterglow measurements by GROWTH-India
  16. GRB 181201A: continued optical observations in TSHAO
  17. GRB 181203A: Swift/UVOT Upper Limits
  18. GRB 181201A: Continued GROND observations show that afterglow is still bright
  19. GRB181201A: GOTO optical observations
  20. GRB 181201A: Swift/UVOT Detection
  21. GRB 181201A: continued optical observations in SAAO and Chilesope
  22. GRB 181202A: RATIR Optical and NIR Observations
  23. GRB 181201A: Further COATLI Optical Monitoring
  24. GRB 181202A: Global MASTER-Net optical observations
  25. GRB 181201A: VLT/FORS2 tentative spectroscopic redshift
  26. GRB 181201A: GROND detection of the afterglow and redshift upper limit of z < 3
  27. GRB 181201A: optical observations in Chilescope observatory
  28. GRB 181201A: Global MASTER-Net prompt optical descovery and afterglow observations
  29. GRB 181202A: Swift detection of a burst with an optical counterpart
  30. GRB 181201A: COATLI Optical Detection
  31. GRB 181201A: Zeiss-1000/CrAO optical observations
  32. GRB 181201A: NOT optical observations
  33. GRB 181201A: optical observations in SAAO
  34. GRB 181201A MASTER-Net OT continued observation
  35. GRB 181201A: iTelescope optical afterglow detection
  36. GRB 181201A MASTER-Net OT detection
  37. GRB 181123B: ATCA 5/9 GHz rapid-response radio observation
  38. GRB 181123B: Keck further near-infrared imaging
  39. GRB 181126A: Swift/UVOT Upper Limits
  40. GRB 181123B: Global MASTER Net optical inspection
  41. GRB 181123B: Keck near-infrared imaging
  42. GRB 181123B: Gemini-North optical detection
  43. GRB 181123B: Swift/UVOT Upper Limits
  44. Swift Trigger 872470: further Swift analysis
  45. GRB 181110A: optical observations in Chilescope observatory
  46. GROND observations of GRB181110A
  47. GRB 181110A: VLT/X-shooter redshift
  48. GRB 181110A: optical observations from iTelescope SSO
  49. GRB 181110A: MITSuME Akeno optical observation
  50. GRB 181110A: Kanata 1.5m optical observation
  51. GRB 181110A: Swift detection of a burst with an optical counterpart
  52. Fermi GRB 181105.31: Global MASTER Net optical observations
  53. GRB 181103A: AbAO optical upper limit
  54. GRB 181103A: MITSuME Okayama optical upper limits
  55. GRB 181103A: Nanshan-1m optical upper limit
  56. GRB 181030A: RATIR Optical and NIR Observations
  57. GRB 181030A: MASTER Net OT detection
  58. GRB 181030A: SAO RAS optical observations
  59. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  60. IceCube-181023A: MASTER Net optical alert and follow up observations
  61. GRB 180728B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 554505003)
  62. GRB 181023A: Swift/UVOT Upper Limits
  63. GRB 181022A: MITSuME Akeno optical upper limits
  64. GRB 181023A: KAIT Optical Upper Limit
  65. GRB 181022A: Swift/UVOT Upper Limits
  66. GRB 181020A: REM detection
  67. Baksan Neutrino BNO 181021: Global MASTER-net Optical Follow-up Observations
  68. GRB 181020A: Swift/UVOT Detection
  69. GRB 181020A: LCO Cerro Tololo observations
  70. GRB 181020A: VLT/X-shooter spectroscopy and redshift
  71. GRB 181020A: Swift detection of a burst with an optical counterpart
  72. FRB 181016: MASTER optical inspection of the Fast Radio Burst error box
  73. GRB 181011A: MITSuME Akeno and Okayama optical upper limits
  74. GRB 181013A: AbAO optical upper limit
  75. GRB 181013A: Swift/UVOT Upper Limits
  76. GRB 181013A: Global MASTER Net optical observations
  77. GRB 181011A: Global MASTER Net optical inspection
  78. GROND afterglow detection of GRB 181010A
  79. GRB 181010A: REM optical and NIR afterglow detection
  80. GRB 181008B: Global MASTER Net optical inspection
  81. GRB 181010A: ePESSTO NTT optical observations
  82. GRB 181010A: VLT/X-shooter redshift
  83. GRB 181010A: RATIR Optical and NIR Afterglow Detection
  84. GRB 181010A: LCO Cerro Tololo observations
  85. GRB 181010A: MASTER-Argentina OT detection
  86. GRB 181010A: Swift detection of a burst with an optical counterpart
  87. GRB 181002A: Mondy optical upper limit
  88. GRB 181003A: RATIR Optical and NIR Observations
  89. GRB 181003A: Swift/UVOT Upper Limits
  90. GRB 180930A: TSHAO optical upper limit
  91. GRB 181003A: MASTER optical observation
  92. GRB181002A: GOTO optical limits
  93. GRB 181002A: Swift/UVOT Upper Limits
  94. GRB 181002A: MASTER optical observation
  95. GRB 180914B: RTT150 optical observations
  96. GRB 180914B: RTT150 optical observations
  97. GRB 180930A: NOT optical upper limits
  98. GRB 180930A: Swift/UVOT Upper Limits
  99. GRB 180930A: KAIT Optical Upper Limit
  100. GRB 180924A: Swift/UVOT Upper Limits

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